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### $\left(0,1\right)$-matrices, discrepancy and preservers

Czechoslovak Mathematical Journal

Let $m$ and $n$ be positive integers, and let $R=\left({r}_{1},...,{r}_{m}\right)$ and $S=\left({s}_{1},...,{s}_{n}\right)$ be nonnegative integral vectors. Let $A\left(R,S\right)$ be the set of all $m×n$$\left(0,1\right)$-matrices with row sum vector $R$ and column vector...

### $\left(-1\right)$-enumeration of self-complementary plane partitions.

The Electronic Journal of Combinatorics [electronic only]

### $2-\left({n}^{2},2n,2n-1\right)$ designs obtained from affine planes

Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica

The simple incidence structure $𝒟\left(𝒜,2\right)$ formed by points and unordered pairs of distinct parallel lines of a finite affine plane $𝒜=\left(𝒫,ℒ\right)$ of order $n>2$ is a $2-\left({n}^{2},2n,2n-1\right)$ design. If $n=3$, $𝒟\left(𝒜,2\right)$ is the complementary design of $𝒜$. If $n=4$, $𝒟\left(𝒜,2\right)$ is isomorphic to the geometric design $A{G}_{3}\left(4,2\right)$ (see [2; Theorem 1.2]). In this paper we give necessary and sufficient conditions for a $2-\left({n}^{2},2n,2n-1\right)$ design to be of the form $𝒟\left(𝒜,2\right)$ for some finite affine plane $𝒜$ of order $n>4$. As a consequence we obtain a characterization of small designs $𝒟\left(𝒜,2\right)$.

### 24 self-inscribed decagons in Desargues configuration ${10}_{3}$

Časopis pro pěstování matematiky

### 2-adic behavior of numbers of domino tilings.

The Electronic Journal of Combinatorics [electronic only]

### $3$-configurations with simple edge basis and their corresponding quasigroup identities

Archivum Mathematicum

There is described a procedure which determines the quasigroup identity corresponding to a given 3-coloured 3-configuration with a simple edge basis.

### 3-designs from PGL$\left(2,q\right)$.

The Electronic Journal of Combinatorics [electronic only]

### 5-sparse Steiner triple systems of order $n$ exist for almost all admissible $n$.

The Electronic Journal of Combinatorics [electronic only]

### A bound on correlation immunity.

Sibirskie Ehlektronnye Matematicheskie Izvestiya [electronic only]

### A Bruhat order for the class of $\left(0,1\right)$-matrices with row sum vector $R$ and column sum vector $S$.

ELA. The Electronic Journal of Linear Algebra [electronic only]

Integers

### A Characterization of Designs Related to the Witt System S(5, 8, 24).

Mathematische Zeitschrift

### A characterization of middle graphs and a matroid associated with middle graphs of hypergraphs

Fundamenta Mathematicae

### A characterization of the bases of line-splitting matroids.

Lobachevskii Journal of Mathematics

### A characterization of the simplex.

Aequationes mathematicae

### A class of latin squares derived from finite abelian groups

Commentationes Mathematicae Universitatis Carolinae

We consider two classes of latin squares that are prolongations of Cayley tables of finite abelian groups. We will show that all squares in the first of these classes are confirmed bachelor squares, squares that have no orthogonal mate and contain at least one cell though which no transversal passes, while none of the squares in the second class can be included in any set of three mutually orthogonal latin squares.

### A Class of Unitary Block Designs.

Mathematische Zeitschrift